Question

A charge, q =-5pC moves through a uniform B-field, B = 0.35 T, with a velocity, v 200 m/s, at right angles to the field. Determine: (a) Fm on the charge; (b) mass of the charge if a 5x 10 m/s.

please I need help

Answer 1

Given $q=-5\mu C=-5*10^{-6}C$

magnetic field, $B=0.35T$

velocity, $v=200m/s$

angle between magnetic field and velocity ,$\theta =90^{\circ}$

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Use Formula $F=qvBsin\theta$

$F=-5*10^{-6}C*200m/s*0.35Tsin90$

$F=-5*10^{-6}*200*0.35*1$

(a)ANSWER: $F=-3.5*10^{-4}N$

negative sign just shows that charge will move in opposite direction as in the case of positive charge

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Use Formula $F=ma$

$-3.5*10^{-4}N=m*-5*10^{4}m/s^{2}$

$3.5*10^{-4}=m*5*10^{4}$

$3.5*10^{-4}/(5*10^{4})=m$

(b)ANSWER: $m=7*10^{-9}kg$

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